1. Field of the Invention
The present invention relates to a back illumination type (back-illuminated) solid-state imaging device receiving light from an opposite side to a surface formed with an interconnection layer, a camera including the same and a method of producing the same.
2. Description of the Related Art
In recent year, in terms of an improvement of an aperture ratio for receiving light and an improvement of a flexibility of a layout of an interconnection layer, a back-illuminated solid-state imaging device in which a semiconductor layer is formed on its surface side with the interconnection layer and illuminated with light from a back surface side thereof to take an image has been known. As the back-illuminated solid-state imaging device, a charged coupled devices (CCD) type and a metal oxide semiconductor (MOS) type have been proposed. For example, the CCD type is disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2002-151673, and the MOS type is disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2003-31785.
If the semiconductor layer formed with a light receiving unit is invaded by metal in a production process of the back-illuminated solid-state imaging device, a crystal defect may occur due to metal to generate an image defect called as a “white scratch”. In order to suppress the image defect, the production process of the back-illuminated solid-state imaging device has to be considered with how to perform a gettering of metal invading the semiconductor layer in the process. A gettering layer for gettering metal is generally formed at outside of an active region of the semiconductor layer.